The National Weather Service in San Diego has noted a slight increase in heat today, with high temperatures remaining a few degrees below normal. For Monday, the city can expect a continuation of this minor warming trend. As per the National Weather Service, moving towards the end of the week, all eyes are on Tropical Storm Priscilla to the south, with uncertainty lingering over whether it will bring moisture into the area. "Taking a look at late next week, we are watching Tropical Storm Priscilla to our south. Uncertainty remains on if any moisture will move into our region."
Meanwhile, residents are waking up to clear skies with a weak marine inversion in place, likely leading to patchy low clouds as a coastal eddy is expected to spin up later this morning. The current weather setup features weak troughing across the Western US and a short wave dropping south through the Pacific Northwest. These conditions suggest highs will be slightly higher today, but a few degrees below normal. "Highs will be a couple degrees higher today but overall a few degrees below normal," NWS San Diego's Area Forecast Discussion reported.
Looking forward, the warming trend will persist into Tuesday, as high pressure builds across the southern United States. San Diego's coastal areas and western valleys should anticipate regions of low clouds and fog throughout the midweek, night, and morning. The big talking point, however, is the potential impact of Tropical Storm Priscilla, which could usher in tropical moisture and a slight chance of showers from late Thursday into Saturday. Despite the tropical connection, instability remains low with "MUCAPE less than 100 J/kg, so thunderstorm probabilities are less than 10%," according to the National Weather Service.
Even so, the forecast remains fluid with respect to rainfall totals. Ensemble predictions point to a range of outcomes, with most indicating modest rainfall, especially given the absence of significant dynamic forcing. "With the low further west, placing us more under the influence of the ridge to the east, accumulating precipitation will be harder to come by," the NWS San Diego's forecast discussion clarifies. Thus, any potential flooding threat seems minimal, with most ensemble members suggesting we're likely to stay on the drier side. Skies should clear by next Sunday as the tropical moisture is pushed out of the region, following the passage of the upper trough.
